2006A&A...445L..15A

Asteroseismology of early A-type stars could be a new tool to test stellar convection theories. A survey for line profile variability in early A-type stars has been performed in order to detect nonradial pulsation signatures. The star HR 6139, with spectral type A2V and estimated T_eff=8800K, shows evident line profile variations that can be explained by oscillations in prograde g-modes. This feature and the known photometric variability are similar to those observed in the Slowly Pulsating B-type stars. However HR 6139 is much cooler than the cool border of the instability strip of such variables, and it is hotter than the blue edge of the δ Scuti instability strip. There are indications of a tiny variability also in other four objects, whose nature is not yet clear.